Choosing eps and minpts for DBSCAN (R)?

Question

I\'ve been searching for an answer for this question for quite a while, so I\'m hoping someone can help me. I\'m using dbscan from the fpc library in R. For example, I am

Answer 1

If you have the resources, you can also test a bunch of epsilon and minPts values and see what works. I do this using expand.grid and mapply.

# Establish search parameters.
k <- c(25, 50, 100, 200, 500, 1000)
eps <- c(0.001, 0.01, 0.02, 0.05, 0.1, 0.2)

# Perform grid search.
grid <- expand.grid(k = k, eps = eps)

results <- mapply(grid$k, grid$eps, FUN = function(k, eps) {
  cluster <- dbscan(data, minPts = k, eps = eps)$cluster
  sum <- table(cluster)
  cat(c("k =", k, "; eps =", eps, ";", sum, "\n"))
})